Researchers around Metin Sitti at Carnegie Mellon University in the US have demonstrated a new way to control micro-robots using a combination of magnets and electrostatic "traps".

In a demonstration three robots only 200 microns, or less than a human hair's width wide, move around on a glass surface. Individual robots can be anchored to this surface using an embedded grid of metal electrodes, which allowed the researchers to individually push micro-spheres in a miniature version of a robotic soccer game.

With further development the researchers hope that this new technology will help pave the way for micro-robots use in drug delivery directly to a sickly cell or a tumor, or allow researchers to fabricate electronics components more easily.